Gah I'm sure I posted this in the wrong section accidentally. Must be blind to the delete button tonight too...
Worry not - I've requested that it be moved to Q&A...
Anyways YES, updating to 4.4.4 will guarantee that you will NEVER be able to root.
If you want details, see the TowelPieRoot thread (in apps/themes sub-forum). It is already out and confirmed working on 4.4.2 (and SOME 4.4.3 variants). It will allow you to tether.
I am a little confused by your title "fake id exploit"? EDIT: just read up on that exploit...wow! Anyways, that exploit does not appear to be capable of gaining root access on a device that doesn't already have the su binary installed. I could definitely be mistaken about that, but after my quick read-up on the details, it appears to only allow one app to masquerade as another. This would appear to mean that an app could only gain root access (once again), if the device is already rooted (su binary installed). It COULD, however, allow a malicious app to bypass a control app like SuperSU, by claiming to be another app you have already granted su access to.
Regardless, my previous statements still apply: see the TowelPieRoot thread if you are interested in rooting...
Good Luck